Agential Realism

A theory coined by Karen Barad, agential realism reconceptualizes the process by which objects are examined and knowledge created in scientific activities. Barad emphasizes that agential realism is not just an epistemological theory, but an ontological one, as it describes how reality is actually shaped.

" [Agential realism] is an epistemological and ontological framework that extends Bohr's insights and takes as its central concerns the nature of materiality, the relationship between the material and the discursive, the nature of "nature" and of "culture" and the relationship between them, the nature of agency, and the effects of boundary, including the nature of exclusions that accompany boundary projects.

Agential realism entails a reformulation of both of its terms - "agency" and "realism" - and provides an understanding of the role of human and nonhuman factors in the production of knowledge, thereby moving considerations of epistemic practices beyond the traditional realism versus social constructivism debates." (89)

Agency, according to Barad, “is a matter of intra-acting; it is an enactment, not something that someone or something has.” (112)

In contrast to similar theories, like Judith Butler's performativity or Foucault's dispositif, agential realism is explicitly not limited to human realm, and so potentially includes nonhumans and cyborgs. (108)

Additionally, Barad emphasizes that matter is not just passive material that is shaped by agents; it undergoes a process as it “stabilizes over time to produce the effect of boundary, fixity, and surface.” (90)

"Crucially, an agential realist elaboration of performativity allows matter its due as an active participant in the world’s becoming, in its ongoing intra-activity. And furthermore it provides an understanding of how discursive practices matter." (136)


This theory arose as a contribution to the existing literature by feminist STS scholars critiquing the lack of attention to important social factors like gender, race, and sexuality, either through omission or through misrepresentation as accepted "natural" categories. The shortcomings of reflexivity, namely that it presumes that reality (social or natural) is merely reflected by representations and that it keeps excessive distance from the world, invited alternative theories centered on diffraction, rather than on reflection.


Barad identifies phenomena as the smallest unit for this intra-action and thus the building blocks for reality, which “is not composed of things-in-themselves or things-behind-phenomena, but things-in-phenomena.” (104) Phenomena represent the inseparability of an object and observations of it.

"In summary, the primary ontological units are not "things" but phenomena - dynamic topological reconfigurings/entanglements/relationalities/(re)articulations of the world." (141)

Niels Bohr's Quantum Physics

“Bohr’s epistemology calls into question several foundationalist assumptions that Western epistemology generally takes as essential to its project; among these are an inherent subject/object distinction and the representational status of language.” (89)

Influential in the development of agential realism was Niels Bohr, a quantum physicist who asserted that observing apparatuses are not merely passive instruments, but things that participate in the formulation of scientific observation. He also resolved the "wave-particle" duality paradox (97) by positing that the paradox existed because the methods used by scientists to measure light as a wave versus as a particle were mutually exclusive.

By granting apparatuses a more active role in the production of knowledge, Bohr challenged the separateness of observer and object by referring to “objects of observation” and “agencies of observation”.

“[T]his interaction between object and apparatus thus forms an inseparable part of the phenomenon.” (95)


“[A]pparatuses are specific material reconfigurings of the world that do not merely emerge in time but iteratively reconfigure space-timematter as part of the ongoing dynamism of becoming."

“...apparatuses are not mere instruments or devices that can be deployed as neutral probes of the natural world, or determining structures of a social nature, but neither are they merely laboratory instruments or social forces that function in a performative mode."

Barad uses the example of the transducer in a sonogram machine that is used to "view" a fetus:

"the transducer does not allow us to peer innocently at the fetus, nor does it simply offer constraints on what we can see; rather, it helps produce and is "part of" the body it images.” (101)

A transducer in a sonogram is not merely a passive instrument; it actively participates in the production of an image of a fetus, both in how it transforms auditory input (sound waves) into visual outputs on a screen, but also in how it makes the fetus seem to be more real and existent than it would have been without.


Another key idea behind agential realism is Barad's emphasis on a transformative and transgressive diffraction, not just reproducing reflection:

"In this regard, it is important not to confuse the fact that I am drawing on an optical phenomenon for my inspiration in developing certain aspects of my methodological approach ... with the nature of the method itself. In particular, calling a method 'diffractive' in analogy with the physical phenomenon of diffraction does not imply that the method itself is analogical. On the contrary, my aim is to disrupt the widespread reliance on an existing optical metaphor - namely, reflection - that is set up to look for homologies and analogies between separate entities. By contrast, diffraction, as I argue, does not concern homologies but attends to specific material entanglements." (87)

Again, Barad's posthumanist expansion of performativity to include nonhumans comes into play:

"I propose a posthumanist performative approach to understanding technoscientific and other naturalcultural practices that specifically acknowledges and takes account of matter’s dynamism. The move toward performative alternatives to representationalism shifts the focus from questions of correspondence between descriptions and reality to matters of practices, doings, and actions." (135)

Barad clarifies that her posthumanism is not celebrating "after humans", but more challenging the prima facie segregation and privileging of humans over and from other beings:

"Posthumanism, as I intend it here, is not calibrated to the human; on the contrary, it is about taking issue with human exceptionalism while being accountable for the role we play in the differential constitution and differential positioning of the human among other creatures (both living and nonliving)" (136)

Hearkening back to her physics roots, Barad compares the conceptual diffraction to optical diffraction versus reflection, explaining that diffraction allows for more insight because it transforms (conceptual) images:

"Such an approach also brings to the forefront important questions of ontology, materiality, and agency, which social constructivist and traditional realist approaches get caught up in the geometrical optics of reflection where, much like the infinite play of images between two facing mirrors, the epistemological gets bounced back and forth, but nothing more is seen.

Moving away from the representationalist trap of geometrical optics, I shift the focus to physical optics, to questions of diffraction rather than reflection. Diffractively reading the insights of poststructuralist theory, science studies, and physics through one another entails thinking the cultural and the natural together in illuminating ways." (135)

This diffraction challenges the singularity and solidity of boundaries, making what was sharply delineated a zone of fuzzy regions that have questionable divisions held in place by iterative performativity:

"What often appears as separate entities (and separate sets of concerns) with sharp edges does not actually entail a relation of absolute exteriority at all. Like the diffraction patters illuminating the indefinite nature of boundaries – displaying shadows in “light” regions and bright spots in “dark” regions – the relationship of the cultural and the natural is a relation of “exteriority within.” This is not a static relationality but a doing – the enactment of boundaries – that always entails constitutive exclusions and therefore requisite questions of accountability." (135)

Comparison to Feminist Epistemological Theories

Barad's position is contrasted with Standpoint Theory and Situated Knowledges because the goal is "not simply to put the observer or knower back in the world (as if the world were a container and we needed to merely to acknowledge our situatedness in it) but to understand and take account of the fact that we too are part of the world's differential becoming" (91). It is also emphasized that agential realism is not just an epistemological theory, but an ontological one, as it emphasizes "not merely that knowledge practices have material consequences but that practices of knowing are specific material engagements that participate in (re)configuring the world" (91). These practices of making knowledge are about making "specific worldly configurations" that engage with the world by giving "specific material form."

Barad, Karen. Meeting the Universe Halfway: Quantum Physics and the Entanglement of Matter and Meaning. Durham: Duke University Press, 2007.
Barad, Karen. “Getting Real: Technoscientific Practices and the Materialization of Reality” Differences, 1998: 10(2), 87-128.

Further reading: